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The observatory of transfers in the vadose zone (OZNS-France) offers a unique support for characterizing the Beauce limestone aquifer at various spatial and temporal scales. This observatory consists of a large well associated with external boreholes dedicated to imaging, monitoring, and understanding mass and heat transfers through the vadose zone. An initial geological characterization of core samples gave valuable information on the facies encountered within the vadose zone. It is composed of highly incoherent limestones down to 7 m-depth and a massive and altered limestone rock layer from 7 to 20 m-depth. The latter presents fracturation and karstification increasing with depth. This study focuses on the hard limestone rock units and aims to quantify the level of heterogeneity through static and dynamic laboratory tests performed on core samples. Along 20 m of three boreholes, representative samples are tested through uniaxial or triaxial conditions. Elastic wave velocities are also measured. The obtained Young's modulus, compression strength, and P- and S-wave velocities highlight strong variations with depth. For example, at 14 m-depth, uniaxial maximal strength ranges from 13 to 123 MPa. In addition, at 16 m-depth, P-wave velocities are distributed from 3,650 to 5,700 m.s−1. These large scatterings confirm the strong heterogeneity of the geological formations. It is interpreted in terms of a high porosity, degree of fracturation and/or initiate active karstification. The double porosity is discussed from the difference between the static and dynamic Young's modulus. Their variations are interpreted in terms of connected porosity and important crack density. This last parameter is estimated from the P- and S- wave velocities, and ranges from 0 to 0.43, with an extremum value of 1.21 around 19 m-depth. These values and variations are in good correlation with log imaging and independent permeability laboratory measurements made on the hard limestone rock units. • Coupled methods allow to characterize transport property of heterogeneous limestones. • Comparison of static and dynamic data shows a strong variation in double porosity. • High heterogeneities are in good correlation with permeability measurements. [ABSTRACT FROM AUTHOR]

Abstract: LIFE Environment/RESPONSE project (2003–2006) aimed to evaluate and map, at regional scale, the impact of climate change on coastal risks (erosion and marine flooding), by anticipating the response to regional climatic change scenarios of coastal systems. These are described by their geomorphology, coastal processes, known hazardous events and existing defences. Application on Aquitaine and Languedoc Roussillon regions (France) assesses the likely increase of the coastal risks. In both regions, the weight of geomorphology and settlement development is underlined. The results point out the need for better knowledge on physical resilience capacity of the coast, assets values and vulnerability, and the urge of an integrated management approach of coastal risk, at least at the scale of sedimentary cell. [Copyright &y& Elsevier]

Abstract: Browsing by mammalian herbivores may help regulate the balance between woody and herbaceous vegetation where agricultural land has been abandoned. Until now, the potential of controlled grazing as a research tool has not yet been fully utilized. In this study, we used an enclosure-based experiment to assess the impact of browsing by red deer on the fate of seedlings on a woodland edge. Species, size, number of lateral shoots, and relative location of seedlings were recorded in 1m2 plots (n =57) distributed among four vegetation types. From autumn 2000 to winter 2002, after the stay of three tame hinds in the enclosure for 5-day periods in each season (a year-round deer density of 15hinds/km2), we checked for loss or browsing damage of seedlings. From autumn 2000 to summer 2001, we additionally recorded the diurnal time spent feeding by the hinds during days 1, 3, and 5, and we simulated their food intake by hand during days 2 and 4. Mortality rates for willow Salix caprea and ash Fraxinus excelsior was higher than for silver fir Abies alba seedlings. Losses due to dehydration, which peaked under coniferous, were counterbalanced by growth of new seedlings. Loss due to browsing was uncommon. Deer impact on coniferous seedlings was insignificant all year long. More broad-leaved seedlings were browsed in spring and summer than in winter. Leader browsing increased with height, most of the taller seedlings occuring in herbaceous vegetation, especially wild cherry Prunus avium. Previously damaged seedlings suffered significantly higher leader browsing than previously undamaged ones. Behavioural observations showed that old pasture was selected by foraging deer all year-round. In autumn, spring and summer, due to quick depletion, the relative contribution of seedlings to the total food intake peaked during day 1, most (>75%) concerning wild cherry. Our results suggest that deer browsing on woody seedlings has more to do with species preference, height structure, growth, and seasonal phenology of seedlings than with induced mortality. Choice of previously damaged seedlings and non-random habitat use by deer can prove useful by minimizing natural regeneration of seedlings close to pastures. Further work is required on long term controlled browsing experiments to better understand natural regeneration of mixed woodland species. [Copyright &y& Elsevier]

Abstract: Analysis of the data collected during the AMMA (African Monsoon Multidisciplinary Analyses) campaign shows that rain storms typical of the African monsoon have multifractal properties, and can be modelled by fractionally integrated multiplicative cascades. The originality of the present study lies in the application of a constraint, which results in the interior only of storms being investigated, such that the multifractal analysis is not affected by the presence of numerous zero values. The model is validated in the time domain by means of disdrometer measurements, and in the spatial domain with co-localized meteorological radar rain maps. The non-conservation parameter obtained in the spatial domain is found to be consistent with the assumption that the rain rate follows a passive scalar-like scaling law up to the scale of storms, including corrections due to fluxes intermittencies. Comparison of the value of this parameter with that obtained in the temporal domain indicates the presence of a space–time anisotropy, which could be explained by turbulent advection. [Copyright &y& Elsevier]

Precipitation of radial hydrides in zirconium-based alloy cladding concomitant with the cooling of spent nuclear fuel during dry storage can potentially compromise cladding integrity during its subsequent handling and transportation. This paper investigates hydride reorientation and its impact on ductility in unirradiated and irradiated recrystallized Zircaloy-2 cladding with an inner liner (cladding for boiling water reactors) subjected to hydride reorientation treatments. Cooling from 400 °C, hydride reorientation occurs in recrystallized Zircaloy-2 with liner at a lower effective stress in irradiated samples (below 40 MPa) than in unirradiated specimens (between 40 and 80 MPa). Despite significant hydride reorientation, unirradiated recrystallized Zircaloy-2 with liner cladding containing ∼200 wppm hydrogen shows a high diametral strain at fracture (>15%) during burst tests at ambient temperature. This ductile behavior is due to (1) the lower yield stress of the recrystallized cladding materials in comparison to hydride fracture strength (corrected by the compression stress arising from the precipitation) and (2) the hydride or hydrogen-depleted zone as a result of segregation of hydrogen into the liner layer. In irradiated Zircaloy-2 with liner cladding containing ∼340 wppm hydrogen, the conservation of some ductility during ring tensile tests at ambient temperature after reorientation treatment at 400 °C with cooling rates of ∼60 °C/h is also attributed to the existence of a hydride-depleted zone. Treatments at lower cooling rates (∼6 °C/h and 0.6 °C/h) promote greater levels of hydrogen segregation into the liner and allow for increased irradiation defect annealing, both of which result in a significant increase in ductility. Based on this investigation, given the very low cooling rates typical of dry storage systems, it can be concluded that the thermal transients associated with dry storage should not degrade, and more likely should actually improve, ductility of recrystallized Zircaloy-2 cladding with inner liner with such hydrogen content. [ABSTRACT FROM AUTHOR]

The present study investigates the sensitivity of laccase activity to the fungicide tebuconazole (TBZ) in order to seek for new functional toxicity descriptors in aquatic microbial communities associated to decomposing litter. With this aim, we analyzed the sensitivity of laccase from the different microbial components (fungi and bacteria growing separately and in co-existence), as well as that of their corresponding enzyme fractions (cell bound and diffusible), forming microbial communities in Alnus glutinosa leaves. Results show that fungi are pivotal for laccase activity in leaves and that their activity is repressed when they co-exist with bacteria. The sensitivity of laccase activity to the TBZ was only detectable in leaves colonized by fungi separately ( Alatospora acuminata populations), but absent in those colonized by bacteria separately and/or mixed fungi plus bacteria. Specifically, the increase of TBZ concentration enhances laccase activity in Alatospora acuminata populations but decreases ergosterol concentration as well as the amount of 18S RNA gene copies. This activity response suggests a detoxification mechanism employed by the fungus in order to reduce TBZ toxicity. Besides, enzyme fractioning showed that laccase activity in the cell bound fraction (76% of the total activity) was sensitive to the fungicide, but not that in the diffusible fraction (24% of total activity). Hence, TBZ would influence laccase activity in the presence of fungal cells but not in enzymes already synthesized in the extracellular space. The present study highlights the importance of the biological complexity level (i. e. population, community, ecosystem) when seeking for appropriate functional ecotoxicity descriptors in aquatic microbial communities. [ABSTRACT FROM AUTHOR]

Triketones, derived chemically from a natural phytotoxin (leptospermone), are a good example of allelochemicals as lead molecules for the development of new herbicides. Targeting a new and key enzyme involved in carotenoid biosynthesis, these latest-generation herbicides (sulcotrione, mesotrione and tembotrione) were designed to be eco-friendly and commercialized fifteen-twenty years ago. The mechanisms controlling their fate in different ecological niches as well as their toxicity and impact on different organisms or ecosystems are still under investigation. This review combines an overview of the results published in the literature on β-triketones and more specifically, on the commercially-available herbicides and includes new results obtained in our interdisciplinary study aiming to understand all the processes involved (i) in their transfer from the soil to the connected aquatic compartments, (ii) in their transformation by photochemical and biological mechanisms but also to evaluate (iii) the impacts of the parent molecules and their transformation products on various target and non-target organisms (aquatic microorganisms, plants, soil microbial communities). Analysis of all the data on the fate and impact of these molecules, used pure, as formulation or in cocktails, give an overall guide for the assessment of their environmental risks. [ABSTRACT FROM AUTHOR]

We propose a new methodology for large-scale urban 3D scene analysis in terms of automatically assigning 3D points the respective semantic labels. The methodology focuses on simplicity and reproducibility of the involved components as well as performance in terms of accuracy and computational efficiency. Exploiting a variety of low-level 2D and 3D geometric features, we further improve their distinctiveness by involving individual neighborhoods of optimal size. Due to the use of individual neighborhoods, the methodology is not tailored to a specific dataset, but in principle designed to process point clouds with a few millions of 3D points. Consequently, an extension has to be introduced for analyzing huge 3D point clouds with possibly billions of points for a whole city. For this purpose, we propose an extension which is based on an appropriate partitioning of the scene and thus allows a successive processing in a reasonable time without affecting the quality of the classification results. We demonstrate the performance of our methodology on two labeled benchmark datasets with respect to robustness, efficiency, and scalability. [ABSTRACT FROM AUTHOR]

Résumé Chez l’enfant, un épanchement articulaire fébrile doit faire suspecter le diagnostic d’arthrite septique (AS) et réaliser une ponction articulaire pour confirmer le diagnostic et effectuer un lavage articulaire. La protéine C-réactive (CRP) est une aide diagnostique mais dans les AS son élévation peut être modérée ou nulle. Dans une étude précédente, 10 % des enfants hospitalisés pour AS à Staphylococcus aureus ou à Kingella kingae avaient un taux initial de CRP normal. Pour déterminer si d’autres paramètres auraient permis de « rattraper » le diagnostic d’AS chez ces patients, nous avons analysé leurs caractéristiques cliniques et biologiques et les avons comparées à celles des enfants hospitalisés pour AS dont le taux de CRP était ≥10 mg/L. Parmi les 89 enfants présentant une AS, 9 (10 %) avaient un taux initial de CRP < 10 mg/L ( K. kingae , n = 5/63 ; S. aureus , n = 4/26). La température et le fibrinogène étaient plus bas dans le groupe CRP < 10 mg/L (respectivement 37,3 °C versus 37,9 °C, p = 0,039 et 4,19 versus 5,72 g/L, p = 0,003). L’âge, la durée d’évolution des signes avant diagnostic, les nombres de leucocytes et de plaquettes étaient similaires. Deux enfants avec une AS à S. aureus n’avaient ni fièvre ni élévation de la CRP ou du fibrinogène. Un enfant avec une AS à K. kingae et un taux de CRP < 10 mg/L, a été réopéré pour une rechute précoce de son arthrite. Devant un premier épisode de mono-arthrite chez un enfant, un taux CRP < 10 mg/L ne peut pas éliminer la possibilité d’une arthrite septique et ne doit pas retarder la prise en charge. Summary Septic arthritis has to be suspected in children with joint effusion and fever so as to perform joint aspiration, which will confirm the diagnosis by bacteriological methods, and to perform surgical treatment by joint lavage. Since development of current molecular methods, such as real-time PCR, Kingella kingae has become the first microbial agent of osteoarticular infections in young children, whereas Staphylococcus aureus is second. C-reactive protein (CRP) is an aid used to diagnose septic arthritis, but its elevation could be moderate. In a previous study, conducted at our hospital, 10% of children hospitalized for S. aureus or K. kingae septic arthritis had a CRP level < 10 mg/L. To determine if diagnosis of septic arthritis could be made by other parameters, we analyzed the clinical and biologic features of these patients and compared them to those of children hospitalized for septic arthritis with initial CRP ≥10 mg/L. Among the 89 children with septic arthritis, 10% ( n = 9) had initial CRP < 10 mg/L ( K. kingae , n = 5/63 ; S. aureus , n = 4/26). Initial temperature and fibrinogen were significantly lower in the CRP < 10 mg/L group than in the other (37.3 °C vs. 37.9 °C, P = 0.039 and 4.19 vs. 5.72 g/L, P = 0.003, respectively). Age, symptom duration before diagnosis, as well as leukocyte and platelet counts were similar in both groups. Two children (2/89 = 2.2%) with S. aureus septic arthritis had no fever, CRP elevation, or fibrinogen elevation. In the CRP-negative group, three of four children with S. aureus arthritis and one of five with K. kingae arthritis had a high CRP level (34, 40, 61, and 13 mg/L, respectively) 3 days after surgery and antibiotic treatment. One child with K. kingae septic arthritis and initial CRP < 10 mg/L needed a second surgical drainage because of relapse of arthritis. In the S. aureus arthritis group, none of the children with initial CRP < 10 mg/L experienced complications, while six of those with initial CRP ≥ 10 mg/L needed a second surgical act or hospitalization in an intensive care unit. While CRP is most often > 10 mg/L during septic arthritis in children, it could be negative in up to 20% of patients in different studies. However, a mild inflammatory syndrome or even a CRP < 10 mg/L cannot exclude diagnosis of septic arthritis. Therefore, a first episode of monoarthritis in children has to be considered as septic arthritis and treatment should not be delayed. [ABSTRACT FROM AUTHOR]

Large-scale coastal monitoring programs are challenging to maintain over time but are necessary to understand and further predict complex coastal evolution and resilience. The 230 km-long Aquitaine coast is a high-energy meso-macrotidal coast composed of beach-dune systems showing dramatic morphological changes at seasonal and interannual scales. This study investigates the alongshore variability in beach-dune response based on a unique 11-year dataset of 41 spaced transects surveyed yearly in spring. The dataset is completed by interspersed autumn LiDAR surveys for seasonal analysis. Several beach-dune morphological descriptors are developed, such as beach-dune volume, beach width and different shoreline proxies delimiting the intertidal zone, the beach face and the dune face. The Aquitaine beach-dune system is characterised by a north-south gradient, from chronically eroding dunes backing low-elevation dissipative beaches in the north, to slowly accreting dunes backing wide beaches in the south, through a range of intermediate beach-dune states. Time- and spatially-averaged shoreline (dune foot position) trend is −0.5 m/year (erosion), with local variations ranging from −5.9 m/year to +2.1 m/year. During the 2013–2014 winter widespread erosion was observed, with the shoreline eroding by 13 m and 8 m on average along the Gironde and Landes coasts, respectively. This dataset provides insight into the timing, magnitude and spatial variability of beach-dune recovery from the outstandingly erosive 2013–2014 winter. We also show that local beach-dune volume is a good proxy for long-term shoreline trend. It is advocated that such large-scale coastal monitoring by means of single beach profiles spaced and distributed along 10–100 km of coast is a cheap and efficient approach to address coastal changes at regional scale, which can bring complementary information to aerial photographs interpretation to determine long-term shoreline evolution trend and thus contribute to support sustainable coastal management and planning. • Analysis of a 11-year beach profile dataset along 230 km of high-energy sandy coast. • All morphological descriptors are characterized by a north-south gradient. • Timing and magnitude of beach-dune recovery from the 2013-14 winter is variable. • Shoreline change trends range from −5.9 m/year to +2.1 m/year. • Post-winter beach-dune volume is a good proxy of shoreline change trend. [ABSTRACT FROM AUTHOR]

Objectifs Décrire les infections ostéoarticulaires (IOA) des nourrissons de moins de 3 mois. Matériels et méthodes Les données ont été collectées rétrospectivement chez tous les enfants âgés de moins de 3 mois hospitalisés pour une IOA sur une période de 11 ans (2004–2015) dans les CHU Debré, Trousseau et Necker (Paris). Résultats Au total, 71 enfants ont été inclus avec un sexe ratio (M/F) de 1,4 et un âge médian de 25 jours [0–90] ; 11 enfants (15,4 %) étaient prématurés, 11 avaient une IOA nosocomiale. Les atteintes les plus fréquentes étaient la hanche (32 % des enfants) et le genou (32 %). Les symptômes étaient la douleur (94 %), l’impotence fonctionnelle (87 %), la fièvre (52 %). Le délai diagnostique médian était de 2 jours [0–15]. Un germe a été identifié chez 51 enfants (72 %) : Streptocoque du groupe B (45 % des germes), S. aureus (23,5 %), E. coli (17,6 %). La CRP médiane initiale était de 31 mg/L [1–226]. Cinq patients (sur 34 avec suivi > à 1 an) ont présenté des séquelles orthopédiques, dont : inégalité de longueur de membre ( n = 3), épiphysiodèse ( n = 2), ostéonécrose ( n = 1). Conclusion Le streptocoque du groupe B est le germe le plus fréquent dans les IOA communautaires du moins de 3 mois. Les séquelles orthopédiques peuvent être sévères justifiant un suivi orthopédique prolongé. [ABSTRACT FROM AUTHOR]

Objectif Décrire les infections ostéo-articulaires (IOA) des nourrissons de moins de 3 mois. Patients et méthodes Les données ont été collectées rétrospectivement chez tous les enfants âgés de moins de 3 mois hospitalisés pour une IOA sur une période de 11 ans (2004–2015) dans les CHU Debré, Trousseau et Necker (Paris). Résultats Au total, 71 enfants ont été inclus avec un sex-ratio (M/F) de 1,4 et un âge médian de 25 jours [0–90] ; 11 enfants (15,4 %) étaient prématurés, 11 avaient une IOA nosocomiale. Les atteintes les plus fréquentes étaient la hanche (32 % des enfants) et le genou (32 %). Les symptômes étaient la douleur (94 %), l’impotence fonctionnelle (87 %), la fièvre (52 %). Le délai diagnostique médian était de 2 jours [0–15]. Un germe a été identifié chez 51 enfants (72 %) : Streptocoque du groupe B (45 % des germes), S. aureus (23,5 %), E. coli (17,6 %). La CRP médiane initiale était de 31 mg/L [1–226]. Cinq patients (sur 34 avec suivi > 1 an) ont présenté des séquelles orthopédiques, dont : inégalité de longueur de membre ( n = 3), épiphysiodèse ( n = 2), ostéonécrose ( n = 1). Conclusion Le streptocoque du groupe B est le germe le plus fréquent dans les IOA communautaires du moins de 3 mois. Les séquelles orthopédiques peuvent être sévères justifiant un suivi orthopédique prolongé. [ABSTRACT FROM AUTHOR]